1860cf0a49
Adds `VerifyApiKey` middleware protecting all API routes with `X-Api-Key` header validation. Wraps `/api/stations`, `/api/stats/searches`, and `/api/prediction` in throttled middleware group (60 req/min). Updates StationSearchTest to use `RefreshDatabase`, adds `meta` assertion checks, and validates `fuel_type` in HTTP request assertions. Removes auth routes from API docs and replaces with API key authentication instructions. Adds `api_secret_key` config option.